Signal-transmitter.



D. G. KNITTBL & W. J. DAVIS.

SIGNAL TRANSMITTER.

APPLIGATION FILED 11111.19, 191s.

Patented Apr. 14, 19141 I VENTORJ Mu. Q1. 18mm Q X 1 -t?1...;,C w=

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D STAS' PATENT UFEKEE.

DAVID G. KNITTEL AND WILLIAM J. DAVIS, OF PITTSBURGH, PENNSYLVANIA,

ASSIGNORS TO AMERICAN FIRE ALARM COMPANY, OF PITTSBURGH, PENNSYL- VANIA, A CORPORATION OF DELAWARE.

SIGNAL-TRANSMITTER.

Specification of Letters Patent.

Patented Apr. 14, 1914:.

Application filed March 19, 1913. Serial No. 755,483.

To all whom it may concern:

Be it known that we, DAVID G. KNITTEL and WILLIAM J. DAVIS, residing at Pitts burgh, in the county of Allegheny and State of Pennsylvania, both citizens of the United States, have invented or discovered certain new and useful Improvements in Signal- Transmitters, of which improvements the following is a specification.

Our invention has to do with the construction and operation of signal stations, such as police reporting boxes, wherein suitable mechanism is provided to transmit variable codes from the box to a central station.

()ne object of our invention is to improve the general construction of the code-transmitting mechanism contained within such boxes, to the end that its operation may be certain and positive at all times.

In the accompanying drawing, which forms part of our specification, we have illustrated an embodiment of our invention.

Figure 1 of the drawing is a side view of a code transmitter and a portion of the reporting boX within which such transmitter is placed, the casing for such transmitter being shown in section; Fig. 2 is a sectional view taken on the line IIII, Fig. 1: and Figs. 3 and 4 are detail views which will be referred to more particularly hereafter.

Like numerals are used to designate like parts.

The general arrangement of the transmitter shown herein is such that the proper setting of an indicator or finger and the pulling of a lever will set in motion instrumentalities whereby an electrical circuit will be interrupted a predetermined number of times, each of such interruptions being efiective to operate a recording instrument or ring a bell at the central station. The signals usually transmitted by such mecha nisms, and which the particular construction shown herein is adapted to transmit, is the number of the box or reporting station, and a special signal, varying according to the circumstances of the call, and predetermined by the positioning of the above mentioned indicator. The mechanism or transmitter for thus interrupting the electrical circuit comprises a rotatable box-number wheel 1, a special signal wheel 9, an arm 15 carrying a circuit closing pen 16 and adapted to be moved by either of said wheels, and a shunted electrical circuit. Referring first to the several said elements of the transmitter in the order named, and subsequently to the circuit which it controls, the box-number wheel 1 is a tooth-provided disk secured to a shaft 2, which, by means of a suitable clock work mechanism 3, is adapted to be revolved one complete revolution upon each operation of the transmitter, said mechanism 8 being placed in motion by turning, through a limited arc, a lever 4 secured to a shaft 5. The detail construction of the clock work 3, being well understood by those skilled in the art, need not be here described. The periphery of the wheel 1 is provided with an extended projection 6 and with a series of teeth 7 corresponding in number and arrangement to the boX number of the particular reporting box in which the transmitter is placed; also, the shaft 2 has a segmental pinion 8 secured to it, and in circun1- ferential arrangement upon said shaft this pinion extends between the end of the projection 6 and the first of the series of teeth 7.

The special signal wheel 9 is secured to a rotatably mounted shaft 10, and is provided upon its periphery with a series of evenly spaced teeth 11. Secured to the same shaft there is also a segmental pinion 12 adapted to be engaged by the pinion 8 of shaft 2, and a tooth provided insulation block 13 adapted to control a shunt circuit, as will appear more fully hereafter. The position of the special signal wheel, in advance of the transmission of a given signal, varies according to the special signal desired to have transmitted, such signals consisting simply in the different number of interruptions of the electrical circuit. In order to set the wheel for a predetermined signal an indicator or finger 30 is rigidly secured to the shaft 10, and a suitably graduated dial (not shown herein) is placed below such finger.

The arm 15, which carries the circuit con trolling pen 16, is pivoted at 17 and bears, through suitable rollers 18 and 19, upon the wheels 1 and 9. As will be readily seen, this arm, which is rigid throughout, is pivoted at one end and bears upon said wheels at points between the contact pen 16 and its pivot point 17. The advantage of this particular construction is that the toothed wheels, operating directly upon the arm which carries the contact pen, cannot throw such arm out of adjustment, thus causing confusion in the signals transmitted.

The electrical circuit, which is opened and closed by the movement of the contact pen 16, extends to the transmitter by electrical conductors 20 and 21, which are connected thereto by suitable binding posts 22 and 23. The binding post 22 is electrically connected successively to binding posts 24 and 25, from the latter of which a contact arm 26 projects to the contact pen 16; and the binding post 23 is similarly connected to posts 27 and 28 from which also extends a contact arm 29. This main electrical circu'it is adapted to be shunted or short circuited by two independent means. In the firstwplace it is desirable to have a path of electrical; continuity, other than through armsz26 and 29 and pen 16, when the transmitteruisinoperative, for the reason that foreignvcu-rrents are liable to burn out such arms) 'which:mare necessarily delicate. To such ian end a contact arm 31 and a springarmicont'act member 32 are secured, respectivelyp't'o bintlih g posts 22 and 23, and an abui't' m'ent '33 iis {=secur.ed {to the shaft 5, the arrangement; being. 'suclr that, when the transmitterzis inoperativefon -at rest, said abutmenttwilljbe efl'ecti v'e to'hol'd the spring arm SQeyiel'din'glyiin' contactw-ith the arm 3" ut, whenithe operating lever l is turned t setiimxmotion theitransmittingmechanism (a'srlieretofoi ezexplained) said {abutment- 33 Faway from thegspring-arm 32*ti1d allows 2 it to breakcontactlfwitlr: the 'arm 31,

1 as';showri1.-in Fig 3x z ls'wilhbe readily un derstiiod, the-Fabutment 33gi a-ft'er' the; trans mitter has been set in. motion, graduallyr turnsfirto 1 its circuit gclosing position. 1 The sprihgf36 carried by thel abutfnent '33,; en: gagesiztheiwheel -9 and holds it yieldingly in itsrscpre-arraiiged position until the trans mitter iss et in;finotion.q"Thesecond of'said shunt ci rcuits isTprovidedfiri order to p're; v'entciwhen' idesired; the: extended wheel pro jetion 'lti g eausinga long warning-ring in"th e' from descriptions of two'i ofithe possi-ble sjig' rials; eff-hezsegeiialsparts16f the transmitter 'signal the indicator 30 is not moved.

by an eentrali'stationin advance -of the "special isigg'g T be closedthrough arm's s aclvanbesa l'armiersignal j by th'e projeot ion" 6; Follqwing theip of said projection beyond the roller; 18 th d b-lock 13 forirall isignalsi'.ma nzibe clearly understood are shown in normal inoperative position in Fig. 2 of the drawings, and in this position it will be seen that the abutment 33 is effective to close the circuit through contact arm 31 and spring arm 32, and that the movement of the pen 16, caused by the setting of the special signal wheel 9, will therefore not effect an intermittentbreaking of the circuit.

The simplest signal, which in the particular arrangement of the present disclosure may be sent, is the box number preceded by the long warning alarm. To transmit ill: turning of the lever 4: through its permissible range of movement will be effective to move the abutment 33 and the spring 36 to the position indicated in Fig. 3, wherein the circuit through the arms 31 and 32 is open. When the lever is released the wheel 1 revolves at a constant speed in a counter clock-wise direction, as indicated by the arrow placed thereon. The projection 6 raises the arm 15 and contact-pen 16, thus opening the circuit and causing the long advance alarm to betransmitted. Following the long alarm the several teeth 7 intermittently raise the arm 15 and thereby transmit the box number.

When it is desired to send a special signal and to dispense with the advance long alarm, the indicator 30 is suitably adjusted, and by such adjustment the wheel 9, segmental pinion 12 and insulation block 13 are turned in a counter clock-wise direction. The insulation block 13, arranged on the shaft 10 below the wheel 9, is provided with teeth alternating with the teeth 11 of said wheel, the' arrangement being such that, when the spring arm 35 rests upon I theapoint of a tooth of such block and thereby holds the arm 35 in contact with the arm 34= the roller 19 of arm 15 will lie in a depressionwbetween adjacent teeth 11 of wheel 9; and when the roller 19 is on the jpointflof a toeth ll, the hump of arm 35 will he teeth. 7 It Will' -therefore be seen that as the b'etween adjacent insulation block wheel 9 and iiisulatiori block 13 are moved 'gagementiof'pinion 8 with pinion 12 th"e fcirci 1it w?" e 'simultaneously opened and clesedbythearm '35 anc1 ==pen 16. After thedind'rcator 0 as been set the lever 4 is pju'lle'dj'and w em 1' a as described'above, Dur'" xt d d the arm p wheel ih'olds position h" 'i'rcuiuwill nd '5 so ii'n raised' will beitraiismltted ine x I simultan 'th no upon each of said wheels between its pivot number then follows the special signal and the entire operation is completed.

lVe do not wish to limit ourselves to the details of construction shown herein, for obviously many changes can be made therein by those skilled in the art without departing from the spirit of our invention as defined inthe claims.

We claim as our invention:

1. In a multiple signal transmitter, the combination of an electrical circuit, boxnumber and special-signal wheels, and a single pivoted arm provic ed with a circuitcontrolling contact member, said arm bearing upon each of said wheels, the portion thereof between and including its bearing points upon said wheels being in fixed and immovable relative position.

2. In a multiple signal transmitter, the combination of an electrical circuit, boxnumber and special-signal wheels, and a sin gle rigid arm pivoted at one end and provided at its opposite end with a circuit-coir trolling contact member, said arm bearing point and said contact member and movable thereby.

3. In a multiple signal transmitter, the combination of a main electrical circuit, box-number and special-signal wheels, :1 pivoted arm provided with a circuit-controlling contact member and movable by each of said wheels, a shunt circuit closed while said transmitter is at rest but open during its period of operation, a second shunt circuit, and means for closing said second l shunt circuit during a portion of the period of operation of said transmitter.

4. In a multiple signal transmitter, the combination of a main electrical circuit, box-number and special-signal wheels, a pivoted arm provided with a circuit-controlling contact member and movable by each of said wheels, a normally-open shunt circuit, and means movable with said specialsignal wheel for closing and opening said shunt circuit simultaneously with the closing and opening of said main circuit by said special signal wheel.

In a multiple signal. transmitter, the combination of a main electrical circuit, box-number and special-signal wheels provided on their peripheries with arm-moving teeth, a pivoted arm provided with a circuit-controlling contact member and movable by said teeth on each of said wheels, 21 normally-open shunt circuit, and an insulation block provided on its periphery with teeth alternating with the teeth on said special-signal wheel, said block movable with said special-signal wheel and effective to close and open said shunt circuit simultaneously with the closing and opening of said main circuit by said special-signal wheel.

I11 testimony whereof we have hereunto set our hands.

DAVID Gr. KNITTEL. IVILLIAM J. DAVIS. lVitnesses PAUL N. Gnrrcnnow, FRANCIS J. TOMASSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

